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Full text of "The Cambridge Natural History"

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an the carpus are alternating in position. The toes are five i
both feet, and are very short. There is a hint of commenein.
*' perissodactylism" in the fore - feet at any rate. The brain i
small and the hemispheres smooth.

The Amblypoda, or Amblydactyla, are so called on account o
their short and stumpy feet and toes. They were held by Pro
fessor Cope to be on the direct line of ancestry of both Perisso
dactyles and Artiodactyles, a view which is on the whole no
accepted at present.

As is the case with other groups, the Amblypoda eommencec
existence as a sub-order with relatively small forms such aŁ

FIG. 114.—Skull of Protolambda bathinodon.      x f.     e.a.m, External auditory meatus ;
m, mastoid ; m.f, mastoid foramen.     (After Osborn.)
PantolaTribda,, the most ancient type known, which is in many
respects a transition between the later forms and other groups of
mammals such as the Creodonta.1 The race culminated and
ended in the giant Dinoceras and Coryphodon, and spread into the
Old "World. In spite of their smooth and diminutive brain, these
mammals were able to hold their own and to multiply into many
species and genera; in this they were perhaps aided by their
formidable tusks and by the horns which many of them possessed.
The teeth seem to imply an omnivorous diet, which was quite
possibly an additional advantage in the struggle for existence,
Ifc does not seem to be necessary to divide off the Dinoceratidae
into a sub-order equivalent to the Coryphodontidae as was done
1 Or perhaps rather to the primitive Ungulates Condylarthra.    It is especially
with PervptychMs of that group.